DESCRIPTION: This study is examining the feasibility of flood risk management alternatives to address flooding issues within the Township of Denville. Denville is a municipality located within Morris County, New Jersey which is approximately 25 miles northwest of Newark. The study is focused on the central part of Denville, which is subject to fluvial flooding from the Rockaway River and Den Brook. Township residents and businesses have suffered extensive losses and damage from multiple flooding events in recent decades, including Hurricane Irene in August 2011 and Tropical Strom Ida in September 2021. An integrated feasibility report and environmental assessment will document the analysis and conclusions of the study.
AUTHORIZATION: This study is being conducted under Section 205 of the Continuing Authorities Program (CAP), which does not require individual study authorization.
STATUS: As a part of this study, which is an iterative process, the Project Delivery Team (PDT) has analyzed several different flood risk management alternatives. Throughout the process the PDT has coordinated their work with the New Jersey Department of Environmental Protection (NJDEP), who is the non-Federal sponsor, and the Township of Denville, who is a stakeholder on the project. Alternatives studied to date have included various structural measures such as floodwalls with closure gates, floodwalls in combination with road raisings, and diversion culverts. None of these structural alternatives analyzed were found to be economically justified so they could not move forward.
In addition to the structural alternatives the PDT has also analyzed nonstructural measures such as elevations, wet floodproofing, and dry floodproofing. The nonstructural analysis conducted by the PDT identified multiple groups or clusters of structures within the study area that were economically justified which indicates the benefits outweighed the costs. On November 20th, 2020 the PDT briefed our higher headquarters, USACE North Atlantic Division (NAD), at a Tentatively Selected Plan milestone in which approval was given to advance the nonstructural plan and complete a draft integrated feasibility report and environmental assessment for public release on the fall of 2023.
NAN/NAB is finalizing the Feasibility Report based on comments received from the public comment period which closed December 4, 2023. It is anticipated to have the final feasibility report in April 2024.
CONTACT:
Bethany M. McClanahan P.E., CFM, ENV SP, WEDG
Project Manager
P: (917) 790-8426
Email: Bethany.M.Mcclanahan@usace.army.mil
U.S. Army Corps of Engineers, New York District
Programs and Project Management Division
26 Federal Plaza
New York, NY 10278
CONGRESSIONAL DISTRICTS:
NJ-11